System and method for releasably holding a surgical instrument

Abstract

The invention is directed to a system and method for releasably holding a surgical instrument (14), such as an endoscopic instrument configured for delivery through a small percutaneous penetration in a patient. The instrument comprises an elongate shaft (100) with a pair of mounting pins (116) laterally extending from the shaft between its proximal and distal ends. An instrument holder comprises a support having a central bore (202) and an axially extending slot (204) for receiving the instrument shaft and the mounting pins. A pair of locking slots (206) are cut into the support transversely to and in communication with the axial slot so that the mounting pins can be rotated within the locking slots. The instrument support further includes a latch assembly for automatically locking the mounting pins within the locking slots to releasably couple the instrument to the instrument holder. With this twist-lock motion, the surgeon can rapidly engage and disengage various instruments from the holder during a surgical procedure, such as open surgery, laparoscopy or thoracoscopy.

What is claimed is: 
     
       1. A surgical system comprising: a surgical instrument comprising an elongate shaft with proximal and distal ends, a longitudinal axis therebetween, an end effector on the distal end and a mounting interface;   an instrument holder comprising a support having a body with first and second ends and a coupling interface for engaging the mounting interface of the instrument to releasably couple the instrument to the holder;   a locking assembly for locking the instrument to the instrument holder; and   a manipulator assembly including a drive assembly for manipulating the instrument holder and the surgical instrument therewith;   wherein said instrument holder includes first and second links for coupling the drive assembly with the surgical instrument and for transferring at least two motion actuations from the drive assembly to the instrument, the motion actuations including rotation of the instrument about the longitudinal axis and actuation of the end effector.   
     
     
       2. The surgical system of claim 1 wherein the drive assembly includes a first controllable motor for rotating the instrument about the instrument axis, a second controllable motor for actuating the end effector on the instrument and a third controllable motor for axially translating the instrument, the instrument holder including a third linkage for transferring motion actuation from the third motor to the instrument. 
     
     
       3. The surgical system of claim 1 wherein the instrument holder further comprises one or more electrical feed-throughs for transferring electrical signals to and from the manipulator assembly and the instrument. 
     
     
       4. The surgical system of claim 1 further comprising an input control device located remotely from said surgical instrument, and a servomechanism coupled to the instrument holder and the input control device for remotely controlling the surgical instrument with the input control device. 
     
     
       5. The surgical system of claim 1, further comprising a plurality of different surgical instruments, the surgical instruments sequentially coupleable to the instrument holder so that different instruments may be used during an endoscopic procedure. 
     
     
       6. A method for performing a surgical procedure within a sterile field with a robotic surgical system comprising: releasably coupling a sterile surgical instrument to an instrument holder;   introducing at least a distal end of the surgical instrument through a percutaneous access port in the patient to a target site within a body cavity of the patient;   transferring at least three motion actuations to the instrument from a manipulator assembly through the instrument holder; and   withdrawing the surgical instrument from the target site.   
     
     
       7. The method of claim 6, wherein the instrument has a longitudinal axis and the manipulator assembly includes a drive assembly, the transferring step further comprising translating the instrument along the longitudinal axis in response to input from the drive assembly. 
     
     
       8. The method of claim 6, wherein the instrument has a longitudinal axis and the manipulator assembly has a drive assembly, the transferring step further comprising rotating the instrument about the shaft axis and articulating an end effector on the instrument in response to input from the drive assembly. 
     
     
       9. The method of claim 6 further comprising: providing a first linkage pivotally mounted to an established base about a first axis   holding the surgical instrument in a predetermined position with a second linkage such that a desired remote spherical center of rotation on the instrument is centered on a portion of the instrument and lies on a second axis perpendicular to and intersecting the first axis; and   pivotally connecting the second linkage to the first linkage to constrain movement of the instrument such that the instrument moves in a parallel-plane relationship to the first linkage; and   manipulating the instrument to perform the surgical procedure, the first and second linkages maintaining the remote center of spherical rotation on the instrument in a fixed position relative to the established base.   
     
     
       10. The method of claim 6 further comprising: sensing forces acting against the instrument;   transferring said forces to an input control device, wherein said forces detected by the sensors include gravitational forces acting against said instrument;   determining an orientation with respect to vertical of the instrument; and   sending signals to a servomechanism representing said orientation so as to prevent gravitational forces acting against the instrument from being transferred to the input control device.   
     
     
       11. The method of claim 6 further comprising: removing the instrument from the instrument holder;   releasably coupling a different surgical instrument to the holder; and   introducing at least a distal end of the different instrument to the target site during the surgical procedure.